Check construction



Aug. 11, 1931. P. J. HARRAH ETAL 1,818,250'

CHECK CONSTRUCTION Filed June 28. 1929 5 l@ [q il 12 Z0 E c .D

30 al l/ IL? 54 /7 I f l L- l l 53 INVENTOR.

Patented Aug. 11, 1931 PHILIP J. HARRAH .AND CHESTER I.

HARRAH, OF BLOOMFIELD, NDIAN'A CHECK CONSTRUCTION Applicationy led June 28,

This invention relates to a door check construction.

The chief object of the invention is to provide a check construction which initially will permit the rapid closing of a door through approximately 75 to 85 degrees of closing and then permits closing at a decreased rate and without banging or slamming.

rlhe chief feature of the invention consists in the construction of the hydraulic door check arranged such that the check is normally inoperative during the greater amount of door travel and becomes progressively operative as the door travel gradually decreases in the closing movement of the door. The aforesaid progressive checking action is initially obtainable by the piston in the check encountering a liquid and moving through the same, the initial movement of go the piston taking place through the air occupied portion of the cylinder. The subsequent travel of the piston is arranged to automatically restrict the by-passing of the liquid thro-ugh the piston so that the rate of travel of the piston is decreased and the third and last stage of piston travel occurs under the aforesaid condition as well as in opposiion to the compression of a bumper spring.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

In the drawings Fig. 1 is a perspective view of the upper corner of a door and j amb with a spring and acheck connecting the saine, the check embodying the invention.

F ig. 2 is a similar view showing three successive positions of the door in the closing movement. Fig. 3 is an enlarged central sectional View through the cylinder and piston "4G construction embodying the invention.

1n the drawings 10 indicates a jamb that pivotally supports a door 11, and a spring 12 is conn-ected at opposite ends to each and normally tends to return the door toward 45, the j amb and in closed relation when released from the open position. A bracket 13 herein shown mounted on the door pivotally supports an angle piece 15 as at 16. The angle piece in turn has a threaded engagement with a piston rod 17 and the ad- 1929. Serial No. 374,461.

Athe cover cap 30, and the exterior thereof is formed as at 31 for tool engagement. The central opening 32 in the cover cap is threadl65 ed to receive a piston rod guide member 33 having a tool engageable extension 34 for mounting the same, and said guide member slidably supports the piston rod 17.

Positioned at the opposite end of the cylinder is an extended coil spring 35. In the last portion of the travel of the piston towards that end, said piston compresses the spring which thereupon serves as a bumper or cushion.

The end of the spring which terminates adjacent the' piston herein is shown secured as at 36 to a disk 37 which cooperates with the piston. The piston construction includes a threaded end of the rod 38 that receives' a S0 plate 39 threadedly mountedV thereon. A cup-shaped washer 40 of felt, leather7 rubber,

or the like, has its central portion retained by the washer 39 and another washer 41 against which bears a spring cup 42 locked S5 by a nut 43.

In an air check construction the aforesaid parts are suliicient, but satisfactory operation does not obtain therefrom for some types of doors. The liquid but partially fills the cylinderas indicated at 45 kfor screen and light doors so that the piston in its initial travel passes through theair filled portion of the piston Without any material resistance and then passes through the liquid containing portion of the cylinder. The liquid in that portion of the cylinder passes through a passage 46 which serves as a by-pass and the size of the by-pass determines the rate of travel of the piston through the liquid. This l by-pass controls the second stage of travel of the piston in the cylinder. An adjustment 70 ior the by-passvmay be provided. The liquid entirely fills the cylinder Vfor very heavy doors. Y i

The nut 43 projects beyond the end of the Y stem or rod l? and forms a chamber 44 that communicates with passage t6 having the lateral outlet et? above-the piston7 the chamber 44 constituting the outlet for the' other end of the passage below the piston. The nut 48 is provided with one or more passages 49 that extends from chamber 44 to the er@ terior thereof, and the total cross sectional area of said passages is approximately half ot the cross sectional area of the passage 46 or its lateral extension 47. Then the disk 37 abuts the end of the nut 43 the liquid below the piston can only obtain access to the passage il@ for discharge above the piston'and permit piston travel by said liquid passing through the passage or passages 49 in the nut. Since the cross sectional area of said passages is substantially half that of the passage #t5 the rate ottravel of the piston is substantially decreased over that' pre- 'iously obtained.V The jjiiston while moving under this relatively restricted flow oflluid has its third rate of travel. Y

As theY aforesaid travel continuesY the spring 35 gradually compresses and oli'ers increased opposition to the forward travel of the piston, and this occurs very near the end thereof so that a final cushioning-iis obtained as the laststep otpiston travel.V

As shown clearly in Fig'. 2 the initial closing movement ot the door is .trom the posi-l tion indicated at A to the position indicated Yat B5 and during this amount ot travel the piston moves through the air occupied portion of: the cylinder. The piston :moves throughthe liquid and betere. the nut chamber bypass is sealedAn the door travels 'from position BY to position C. At the point C restricted fluid communication obtains by'reason of the disk o7 and the linalmovement takes place under the aforesaid control and the last or immediate closing of, the door fromV the position C to D occurs with the compression ot and the cushioning by the c sprng rVlie quick closing Thendesirability of this progressively deJ creased ate of door closure is appa-rent when it is ren'iembered that the rapid door movement takes place during the greater part ot' door movement so that for screen doors the doors are rapidly moved to substantiallyf closed position and then are gradually eased into closed position without slamming or banging'. Vlhen applied to storm doors the result is the same. The door opening is substantially closed with a rapid movement and then the .final closing is but little in amount and relatively noiseless.

ot the door into substantially closed position substantially prevents the admission oitl flies, etc.7 when the cheek is associated with the screen door and cold air when the check is associated with a storm door.

Since the springs only opposes door closing movement, in door opening movement it is not effective for any cushioning or opposition, also the liquid displaced by the piston in its return movement oiters little or no resist-ance, consequently door opening is sulstantially instantaneous and eli'ortless.

The invention claimed is:

l. The combination with two swingingly connected members, ot a check construction connected at one end to one member and at its other end to the other member and including a liquid containing cylinder,` a piston therein, a rod supporting' the same and extending beyond the cylinder, a restricted con'imunication through the piston and bumper spring interposed between the piston and the end of the cylinder opposite the rod supporting end and effective near the end ot the piston travel Jfor cushioning the same, said cylinder being but partially llled with liquid for relatively tree movement oi the piston through the air containing` portion ot' the cylinder.

2. A check construction including a cylinder, a piston rod extending through one end thereof7 a piston in the cylinder and on the tree end ot the rod, an adjustable bypass permitting restricted con'nnunication between the chambers upon opposite sides ot' the piston, an auxiliary chamber at the piston end of the rod freely communicating with the by-pass and having an open end, passage means con'm'mnicating with the auxiliary chamber and insuring communication to the auxiliary chamber at all times, a bumper spring in the cylinder operatively engageablc by the piston, and means carried by said spring' for sealing the open end oi" the chamber near the end ot the piston travel for retarding the rate of piston travel.

.ln witness whereof, we have hereunto aHX-ed our signatures .PHLIP J. HARRAH. CHESTER P. HARRAH. 

